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GETTYDEFS

NAME

gettydefs - speed and tty settings used by getty

DESCRIPTION

The file
/etc/gettydefs
contains information used by
getty(1m)
to set up the speed and tty settings for a line. It supplies
information on what the
login-prompt
should look like. It also supplies the speed to try next if
the user indicates the current speed is not correct by typing a
<break>
character.

Each entry in
/etc/gettydefs
has the following :

label# initial-flags # final-flags # login-prompt #next-label

Each entry is followed by a blank line. Lines that begin with
#
are ignored and may be used to comment the file. The various
fields can contain quoted characters of the form
\b, \n, \c, etc., as well as \nnn,
where
nnn
is the octal value of the desired character. The various fields are:

label

This is the string against which
getty
tries to match its second argument. It is often the speed, such as
1200,
at which the terminal is supposed to run, but it needn't be (see below).

initial-flags

These flags are the initial
ioctl(2)
settings to which the terminal is to be set if a terminal type is
not specified to
getty.
Getty
understands the symbolic names specified in
/usr/include/termio.h
(see
termio(7)).
Normally only the speed flag is required in the
initial-flags
field.
Getty
automatically sets the terminal to raw input mode and takes care of
most of the other flags. The
initial-flag
settings remain in effect until
getty
executes
login(1m).

final-flags

These flags take the same values as the
initial-flags
and are set just prior to
getty
executes
/bin/login.
The speed flag is again required. The composite flag
SANE
takes care of most of the other flags that need to be set so that
the processor and terminal are communicating in a rational fashion.
The other two commonly specified
final-flags
are
TAB3,
so that tabs are sent to the terminal as spaces, and
HUPCL,
so that the line is hung up on the final close.

login-prompt

This entire field is printed as the
login-prompt.
Unlike the above fields where white space is ignored (a space,
tab or new-line), they are included in the
login-prompt
field.

The
login-prompt
may contain various
@char
and
\char
parameters. These are described in full in the
getty(1m)
section PROMPT SUBSTITUTIONS.

next-label

This indicates the next
label
of the entry in the table that
getty
should use if the user types a
<break>
or the input cannot be read. Usually, a series of speeds are linked
together in this fashion, into a closed set. For instance,
2400
linked to
1200,
which in turn is linked to
300,
which finally is linked back to
2400.
If
getty
is called without a
speed
argument, then the first entry of
/etc/gettydefs
is used, thus making the first entry of
/etc/gettydefs
the default entry. It is also used if
getty
can't find the specified
label.
If
/etc/gettydefs
itself is missing, there is one entry built into
getty
which will bring up a terminal at 9600 baud.
It is strongly recommended that after making or modifying
/etc/gettydefs,
it be run through
getty
with the check (-c) option to be sure there are no errors.